Low cost evaporative cooling systems were developed and investigated for their cooling efficiency to improve the shelf life of tomatoes. Average cooling efficiencies of bamboo jute and pot in pot coolers before being loaded with tomatoes were 82% and 79% and after being loaded were 67.6% and 61.6%, respectively. Physiological weight losses were 1.03%, 1.32% and 1.42% for bamboo jute, pot in pot coolers and ambient storage, respectively. The sensory results revealed that the shelf life of tomatoes were 5, 19 and 21 days for ambient, pot in pot and bamboo jute coolers, respectively. Storage type has significant difference on cooling efficiency but not on physiological weight loss, physical damage, freshness and rot incidence at p < 0.05. Thus, both evaporative coolers were found to be energy efficient, environmentally sound and can be used in areas where there is no electricity to improve the shelf life of tomatoes.
Keywords: cooling efficiency, evaporative cooling, postharvest loss, shelf life, tomatoes